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            <div><h3 class="title">
                <a name="asio.reference.yield_context"></a><a class="link" href="yield_context.html"
                                                              title="yield_context">yield_context</a>
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    <p>
        <a class="indexterm" name="asio.indexterm.yield_context"></a>
    </p>
    <p>
        Context object that represents the currently executing coroutine.
    </p>
    <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">basic_yield_context</span><span
            class="special">&lt;</span> <span class="identifier">unspecified</span> <span
            class="special">&gt;</span> <span class="identifier">yield_context</span><span class="special">;</span>
</pre>
    <h5>
        <a name="asio.reference.yield_context.h0"></a>
        <span><a name="asio.reference.yield_context.types"></a></span><a class="link"
                                                                         href="yield_context.html#asio.reference.yield_context.types">Types</a>
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            <colgroup>
                <col>
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                <th>
                    <p>
                        Name
                    </p>
                </th>
                <th>
                    <p>
                        Description
                    </p>
                </th>
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            </thead>
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                <td>
                    <p>
                        <a class="link" href="basic_yield_context/callee_type.html"
                           title="basic_yield_context::callee_type"><span
                                class="bold"><strong>callee_type</strong></span></a>
                    </p>
                </td>
                <td>
                    <p>
                        The coroutine callee type, used by the implementation.
                    </p>
                </td>
            </tr>
            <tr>
                <td>
                    <p>
                        <a class="link" href="basic_yield_context/caller_type.html"
                           title="basic_yield_context::caller_type"><span
                                class="bold"><strong>caller_type</strong></span></a>
                    </p>
                </td>
                <td>
                    <p>
                        The coroutine caller type, used by the implementation.
                    </p>
                </td>
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    <h5>
        <a name="asio.reference.yield_context.h1"></a>
        <span><a name="asio.reference.yield_context.member_functions"></a></span><a class="link"
                                                                                    href="yield_context.html#asio.reference.yield_context.member_functions">Member
        Functions</a>
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                        Name
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                    <p>
                        Description
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                <td>
                    <p>
                        <a class="link" href="basic_yield_context/basic_yield_context.html"
                           title="basic_yield_context::basic_yield_context"><span class="bold"><strong>basic_yield_context</strong></span></a>
                        <span class="silver">[constructor]</span>
                    </p>
                </td>
                <td>
                    <p>
                        Construct a yield context to represent the specified coroutine.
                        <br> <span class="silver"> —</span><br> Construct a yield context from another yield context
                        type.
                    </p>
                </td>
            </tr>
            <tr>
                <td>
                    <p>
                        <a class="link" href="basic_yield_context/operator_lb__rb_.html"
                           title="basic_yield_context::operator[]"><span class="bold"><strong>operator[]</strong></span></a>
                    </p>
                </td>
                <td>
                    <p>
                        Return a yield context that sets the specified error_code.
                    </p>
                </td>
            </tr>
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    </div>
    <p>
        The <a class="link" href="basic_yield_context.html" title="basic_yield_context"><code
            class="computeroutput"><span class="identifier">basic_yield_context</span></code></a>
        class is a completion token type that is used to represent the currently
        executing stackful coroutine. A <a class="link" href="basic_yield_context.html"
                                           title="basic_yield_context"><code class="computeroutput"><span
            class="identifier">basic_yield_context</span></code></a> object may be
        passed as a completion token to an asynchronous operation. For example:
    </p>
    <pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span
            class="keyword">typename</span> <span class="identifier">Handler</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">my_coroutine</span><span class="special">(</span><span
                class="identifier">basic_yield_context</span><span class="special">&lt;</span><span class="identifier">Handler</span><span
                class="special">&gt;</span> <span class="identifier">yield</span><span class="special">)</span>
<span class="special">{</span>
  <span class="special">...</span>
  <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span
                class="identifier">n</span> <span class="special">=</span> <span
                class="identifier">my_socket</span><span class="special">.</span><span class="identifier">async_read_some</span><span
                class="special">(</span><span class="identifier">buffer</span><span class="special">,</span> <span
                class="identifier">yield</span><span class="special">);</span>
  <span class="special">...</span>
<span class="special">}</span>
</pre>
    <p>
        The initiating function (async_read_some in the above example) suspends the
        current coroutine. The coroutine is resumed when the asynchronous operation
        completes, and the result of the operation is returned.
    </p>
    <h5>
        <a name="asio.reference.yield_context.h2"></a>
        <span><a name="asio.reference.yield_context.requirements"></a></span><a class="link"
                                                                                href="yield_context.html#asio.reference.yield_context.requirements">Requirements</a>
    </h5>
    <p>
        <span class="emphasis"><em>Header: </em></span><code class="literal">asio/spawn.hpp</code>
    </p>
    <p>
        <span class="emphasis"><em>Convenience header: </em></span>None
    </p>
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            <div class="copyright-footer">Copyright © 2003-2022 Christopher M. Kohlhoff<p>
                Distributed under the Boost Software License, Version 1.0. (See accompanying
                file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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